VISUAL ACUITY MEASUREMENT

The patient's visual acuity should be measured with their present Rx monocularly and binocularly at distance and near.  The uncorrected distance acuity should be measured.

Usually only high contrast acuity is measured.  Low contrast, contrast sensitivity function and other acuity measurements can be made but are not considered here.

Use proper technique:

	use proper lighting
	be sure charts are properly calibrated
	be sure patient does not "squint" 
    (narrow palpebral apertures)
		(watch patient during testing)
	doctor or technician should hold cover 
    paddle so eye is completely occluded.
	both eyes should be kept open when 
    measuring monocular acuity